Modern ICs have helped to integrate electronic circuitry to decrease size and cost. As a consequence, modern ICs can form complex circuitry and systems. For example, virtually all of the functionality of a system may be realized using one or a handful of ICs. Such circuitry and systems may receive and operate on both analog and digital signals, and may provide analog and digital signals.
The result has been a growing trend to produce circuitry and systems with increased numbers of transistors and similar devices. The growth in the number of devices usually leads to an increase in power consumption or power dissipation. Even for a device with a relatively modest number of devices, the power consumption may place a drain on the power source.